A:3种
B:4种
C:5种
D:6种
-- I heard that there are a few seats left for tonight's show.
-- Really? I was under the impression ______ they were sold out a long time ago.
自来水厂常用电解饱和食盐水制备消毒剂Cl2,反应的化学方程式为:
2NaCl+2H2O 2NaOH+Cl2↑+H2↑.现需要71t氯气用于自来水消毒,理论上需要含杂质10%的粗盐多少吨?